I have two JSON documents that I want to assert equal for Jest unit testing. They should be equal, except the second one has one more key: _id.
Example:
doc1.json
{
username: 'someone',
firstName: 'some',
lastName: 'one',
}
doc2.json
{
_id: '901735013857',
username: 'someone',
firstName: 'some',
lastName: 'one',
}
My code currently looks like this:
const result = await activeDirectoryUserCollection
.findOne({username: testUser1.username});
expect(result).toBe(testUser1);
Obviously this gives the error that they are not equal, just because of that one value.
I'm looking for an alternative to .toBe() that doesn't completely compare the docs, but checks if one is a subset of another. (or something like that).
Alternatively I would appreciate someone to point me to a module that could help me out.
I would checkout Lodash module's .isMatch function.
It performs a partial deep comparison between object and source to determine if object contains equivalent property values.
https://lodash.com/docs/4.17.11#isMatch
Example:
var object = { 'a': 1, 'b': 2 };
_.isMatch(object, { 'b': 2 });
// => true
_.isMatch(object, { 'b': 1 });
// => false
You can iterate through one Object and use the key to assert value in both Objects. Read More for...in
const result = await activeDirectoryUserCollection
.findOne({username: testUser1.username});
for (const prop in testUser1) {
if (testUser1[prop]) {
expect(result[prop]).toBe(testUser1[prop]); // or use .toEqual
}
}
I don't think you need to look outside jest for this. You can use expect.objectContaining(), which is described in the docs as:
expect.objectContaining(object) matches any received object that recursively matches the expected properties. That is, the expected object is a subset of the received object. Therefore, it matches a received object which contains properties that are present in the expected object.
You could use it like:
test('objects', () => {
expect(doc2).toEqual(
expect.objectContaining(doc1)
);
});
Related
I'm working on a JS project where I need to override some values in my object which contains nested objects.
I'd normally use the following:
const merged = { ...application, ...customer }
So that any data inside of customer can override the application.
However, in my example, customer is overriding the entire applicant nested object and I just need to override the name within that object?
I've put together a JS fiddle which can be found here, what am I missing?
const customer = {
applicant: {
first_name: 'john'
}
}
const application = {
applicant: {
first_name: 'edward',
age: 50
},
income: {
salary: 500
}
}
const merged = { ...application, ...customer }
console.log(merged)
In merged I expect the first_name to be "John" whilst everything else remains in tact.
The properties you want to replace via spreading have to be at the top level of the object. In this case you take the top-level properties of application, which are applicant and income, and then replace the applicant property with that from customer. If you want the name to be replaced you would need something like
const merged = {
...application,
applicant: {...application.applicant, ...customer.applicant}
};
You can do this easily with lodash
const merged = _.merge(customer, application)
https://lodash.com/docs/4.17.15#merge
I have a simple scenario where I am trying to update an array value that is part of an object, but the object does not seem to reflect the update.
Code:
var request =
{
description: 'my-desc',
details: []
};
request.details['shelf-info'] =
[
{
key: 'ShelfNumber',
value: '100'
}
];
console.log(JSON.stringify(request))
With the assignment of shelf-info, I would have expected the resulting output to be similar to:
Desired Output:
{ "description": "my-desc", "details": { "shelf-info": [ "key": "ShelfNumber", "value": "100" ] } }
but the update doesn't seem to have taken effect:
Actual Output:
{"description":"my-desc","details":[]}
I have found that I can add simple objects (strings) to an array using append, but shelf-info may or may not already be in the request.details section by the time this code gets executed...how would I handle both cases?
You want a plain object ({}) for details, not an array ([]).
When arrays are serialized to JSON, the JSON output only includes values that are stored in whole-number indices. Arrays may validly have other properties whose key names are not non-negative integers (such as the string shelf-info) but those properties are not included the JSON serialization of the array.
You're using an array as if it's an object, which it technically is, but that won't add anything to the array, and it won't convert the array to a regular object with key/value pairs.
Easy fix:
var request = {
description: 'my-desc',
details: { }
};
Also since it's 2020 you should be using let instead of var in most cases.
Try Below. Detail property should be an object.
var request =
{
description: 'my-desc',
details: {}
};
request.details['shelf-info'] =
[
{
key: 'ShelfNumber',
value: '100'
}
];
console.log(JSON.stringify(request))
I have an array, clients, which I want to run array.find() on. This array contains objects, and usually looks something like this:
[ { customId: 'user1', clientId: 'TPGMNrnGtpRYtxxIAAAC' },
{ customId: 'user2', clientId: 'G80kFbp9ggAcLiDjAAAE' } ]
This is where I encounter a problem. I am trying to use find() to see if any object (or part of an object) in the array matches a certain variable, recipient, which usually contains a value like user1. the code I am using to do this is:
function checkID(recipient) {
return recipient;
}
var found = clients.find(checkID);
This always returns the first object in the array. Am I using find() wrong, or is there a better way to do this?
find takes a predicate (a function that returns true if item is a match and false if item is not a match).
const arr = [ { customId: 'user1', clientId: 'TPGMNrnGtpRYtxxIAAAC' },
{ customId: 'user2', clientId: 'G80kFbp9ggAcLiDjAAAE' } ]
const result = arr.find(item => item.customId === 'user1')
// ^^^^^^^^^^^^^^^^^^^^^^^^^
// This should evaluate to true for a match and to false for non-match
The reason you're getting the first item of your array all the time, is because your checkId function is returning something which evaluates to true. So, the first item is evaluated and produces a truthy result, and therefore it gets picked as the first match.
If unfamiliar with the lambda syntax () => {}, then that line is similar to:
const result = arr.find(function (item) { return item.customId === 'user1' })
You are using find wrong.
If recipient contains information about the target value you should name the first param of checkID with a different name. And compare any property of it with recipient.
var found = clients.find(function(element) { return element.prop1 === recipient.anyProp; });
To check the objects in the array for the presence of a certain customId, put the value you're searching for in an object, and pass that object to find():
let clients = [{
customId: "user1",
clientId: "TPGMNrnGtpRYtxxIAAAC"
},
{
customId: "user2",
clientId: "G80kFbp9ggAcLiDjAAAE"
}
];
function checkID(el){
return el.customId === this.param;
}
let found = clients.find(checkID, {param: "user1"});
console.info(found);
So I have this code in vue:
export default {
name: 'Test',
data() {
return {
test1: ['1', '2', '3'],
test2: [{
name: 'Hello'
}, {
name: 'Number two'
}, {
name: 'What ever'
}],
};
},
created() {
const first = [...this.test1];
first.forEach((elm, index) => first[index] = 'New');
console.log('first: ', first);
console.log('test1 in data', this.test1);
const second = [...this.test2];
second.forEach(elm => elm.name = 'New');
console.log('second: ', second);
console.log('test2 in data', this.test2);
},
}
After setting the value of each item of the array 'first' (that should be a copy without reference to the data 'test1' array) each item is equal to 'new'. The value of this.test1 doesn't change.
I did the same with test2. Copied and changed the value of each item to 'New'. But now the value of the data array 'test2' also has 'New' in every item.
I have no clue why this is like that. Any ideas?
Spread syntax creates a shallow copy. If your array has primitive types like numbers or strings, it won't update the original array. That's the case with test1. In the second case, only a new array is created. If you push or pop from the array, original array won't be updated. But, the objects are still pointing to their same place in memory. Updating them will update original array's objects as well.
You can use the spread syntax on the individual object to create a copy of the objects:
const second = this.test2.map(o => ({...o}))
You can also use JSON.parse and JSON.stringify. But, if the objects have any function properties, they'll be removed.
const second = JSON.parse(JSON.stringify(this.test2))
The reason it is like that is because you are having an array of Vue data values. So even though you are cloning the Array, you are also copying over each values 'getters' and 'setters' which have a reference to the original array. In order to remove the getters and setters you should do what d-h-e has suggested.
You could also do this.
const second = this.test2.map(() => { name: 'New' } );
console.log('second: ', second);
console.log('test2 in data', this.test2);
Try it with:
const second = JSON.parse(JSON.stringify(this.test2));
The copy method with spreadoperator or Array.from works only with simple arrays.
For deep copy use the method with JSON.parse and JSON.stringify.
I have associative array.
It's a key(number) and value(object).
I need to keep state of this array same as it is I just need to update one object property.
Example of array:
5678: {OrderId: 1, Title: "Example 1", Users: [{UserId: 1}, {UserId: 2}, {UserId: 3}]}
5679: {OrderId: 2, Title: "Example 2", Users: [{UserId: 1}, {UserId: 2}, {UserId: 3}]}
I need to update Users array property.
I tried this but it doesn't work:
ordersAssociativeArray: {
...state.ordersAssociativeArray,
[action.key]: {
...state.ordersAssociativeArray[action.key],
Users: action.updatedUsers
}
}
This is data inside reducer.
What I did wrong how to fix this?
Something that might help.
When I inspect values in chrome I check previous value and value after execution of my code above:
Before:
ordersAssociativeArray:Array(22) > 5678: Order {OrderId: ...}
After:
ordersAssociativeArray: > 5678: {OrderId: ...}
Solution (code in my reducer)
let temp = Object.assign([], state.ordersAssociativeArray);
temp[action.key].Users = action.updatedUsers;
return {
...state,
ordersAssociativeArray: temp
}
So this code is working fine.
But I still don't understand why? So I have solution but would like if someone can explain me why this way is working and first not?
If it could help here how I put objects in this associative array initialy:
ordersAssociativeArray[someID] = someObject // this object is created by 'new Order(par1, par2 etc.)'
What you are doing is correct, as demonstrated by this fiddle. There may be problem somewhere else in your code.
Something that I would recommend for you is to separate your reducer into two functions, ordersReducer and orderReducer. This way you will avoid the excessive use of dots, which may be what caused you to doubt the correctness of your code.
For example, something like:
const ordersReducer = (state, action) => {
const order = state[action.key]
return {
...state,
[action.key]: orderReducer(order, action)
}
}
const orderReducer = (state, action) => {
return {
...state,
Users: action.updatedUsers
}
}
I hope you find your bug!
Update
In your solution you use let temp = Object.assign([], state.ordersAssociativeArray);. This is fine, but I thought you should know that it is sometimes preferable to use a {} even when you are indexing by numbers.
Arrays in javascript aren't great for representing normalized data, because if an id is missing the js array will still have an undefined entry at that index. For example,
const orders = []
array[5000] = 1 // now my array has 4999 undefined entries
If you use an object with integer keys, on the other hand, you get nice tightly packed entries.
const orders = {}
orders[5000] = 1 // { 5000: 1 } no undefined entries
Here is an article about normalizing state shape in redux. Notice how they migrate from using an array in the original example, to an object with keys like users1.
The problem can be that you're using array in the state but in the reducer you're putting as object. Try doing:
ordersAssociativeArray: [ //an array and not an object
...state.ordersAssociativeArray,
[action.key]: {
...state.ordersAssociativeArray[action.key],
Users: action.updatedUsers
}
]
It will put ordersAssociative array in your state and not an object.